Features

When is the last time you went into a farm shop and thought 'This is amazing'?

That was the case when I visited Keelham Farm Shop on the outskirts of Skipton, Yorkshire. David Haughton and Ken Riley fromDK Heat Recovery invited me up to see how they are helping this outstanding farm shop use heat recovery from its refrigeration systems to generate hot water and heating to save hundreds of pounds a month off their energy bill.

Keelham Farm Shop is a privately-owned business with two shops in its group. The owners supply the shops from their own farm and 400 other local farms. The Skipton shop is an impressive building which includes the shop, a cafe and restaurant, bakery, flower shop, butchers and an ale house. It opened in June 2015 and its owners were keen to ensure that it was environmentally friendly and efficient.

​It is a busy place with shoppers and visitors to the cafe. The shops has a range of retail refrigeration pack systems for the fresh produce, which Franchillinstalled and commissioned. The shop needs not only refrigerated produce but also hot water for the kitchen, butchery and wash rooms. In addition, the offices need heat to keep them comfortable.

​The heat recovery system

The DK Heat Recovery tanks in the plant room

​Heat from the refrigeration systems is recovered using three DK Heat Recovery heat exchangers in a 750 litre storage tank provides 24kW of heat recovery. DK's system can provide over 500 litres of hot water per hour. For the heating system, there is a 300 litre buffer tank which includes a 12kW heat exchanger.

Ken Riley explained that the DK heat exchangers have a patented design which separates the refrigerant from the water. This means it meets the EN1717 legislation, which is required for businesses handling food.

The heat exchanger's simple design is effective. It can remove up to 100% of the heat produced by the refrigeration plant. However, at the Keelham Farm Shop, David said they use only about a quarter of the heat available. The team at Franchill were keen not to 'over-condense' the system and affect the compressors. The heat recovery system was designed to avoid that and be the slave to the refrigeration plant.

How quickly will it payback?

​To keep track of costs, the owners asked for a heat meter to be fitted so they could keep an eye of the amount of hot water being used. Since installing the heat recovery system, the farm shop has saved around £500 per month on its energy bills.

​Heat recovery systems like this can pay for themselves quickly. Payback for hot water systems is usually between two and three years, according to Ken. The best results they achieved on a heat recovery system was 171 days. Payback for heating systems is usually between five and six years. It takes longer because it is not used all year round.

The Keelham Farm Shop system for hot water will pay for itself within two years. In its first four weeks of trading, the DK heat recovery system saved 4,700 kWh and provided 140,000 litres of hot water. And, its carbon footprint has dropped by 25 tonnes a year.

Why is heat recovery not more widely used?

The heat exchanger within the DK systems

​Heat recovery is popular with food retailing businesses. They usually need lots of hot water water and they have a heavy refrigeration demand. Heat recovery in Europe is used more widely than in the UK. That's partly because fossil fuel prices have plummeted recently because of the amount of shale gas available on the market.

Also, the UK government focuses on subsidies for renewable power generation and renewable heat. There is no focus on heat recovery or energy reduction, which is puzzling, at best.

On top of that, most food businesses, especially supermarkets, do not want to spend their capital budgets on energy saving equipment which does not provide returns now. Why? Because they are always short on capital budget, which means they prefer to invest in projects which increase their production.

​However, with heat recovery, as mentioned above, paybacks can be surprisingly quick. And, businesses can pay for their energy once and use all of it or most of it twice. Installers who understand the principles of heat recovery, and that they can help their customers get free hot water, stand to do well out of the technology.

It is relatively simple to connect to existing refrigeration kit. The equipment can be installed in winter in the refrigeration and air conditioning 'off-season', providing additional business. And, the margins are pretty good too, apparently.

Benefits without the red tape

​Keelham Farm Shop is benefiting well from heat recovery. There's no RHI subsidy for this installation, but it does not matter. This Yorkshire business is driving costs out of its business and providing great value to its customers (A huge punnet of English strawberries was only £2, for instance).

With some clever DK Heat Recovery kit, the owners are not making use of the heat from the cooling to keep their customers comfortable while the produce stays fresh. It is the laws of physics at work without having to fill out the paperwork associated with the Renewable Heat Initiative.